Process for continuously sterilizing milk and the like



vAlume 16, 1925.

N J. NIELSEN PROCESS FOR GONTINUOUSLY STERILIZING MILK AND THE LIKE Filed June 28, 192% Patented June 16, 1925.

UNITED TATES NIELS JO'NAS NIELSEN,

or AARHUS, DENMARK.

PROCESS FOR CONTINUOUSLY STERILIZING MILK AND THE LIKE.

Application filed June 28, 1924. Serial No. 723,025.

To all whom it my concern.

Be it known that I, NIELS J ONAS NIELSEN, manufacturer, a subject of the King of Denmark, residing at 15 Frederiksgade, Aarhus, Denmark, have invented certain new and useful Improvements in or Itelatin to Processes for Continuously Sterilizing Milk and the like, of which the following is a specilication.

My present invention relates to processes for-sterilizing milk or similar liquids by continuously passing the liquid through a heated tube system or.the like under pressure.

The object of my invention is to reduce the consumption of heat, for instance, steam, and also to reduce' the consumption of cold in the case of usin after the heating tube system a cooling tu e system or the like in which the sterilized milk is being cooled down to about ordinary temperature in order to be filled in transport cans or the like.

The invention consists chiefly in. enabling the hot milk under pressure to boil by passing it through a chamber of lower pressure that is ordinary air pressure, and allowing the milk va ours thus developed to be condensed in tlie milk passing to the heating system.

Through the evaporation, the hot milk is deprived of a certain heat quantity depending on the difference between the pressure or the temperature in the heating system and the pressure or the temperature in the evaporation chamber. Through the condensation of the milk vapours in the fresh milk, a corresponding heat uantity is transferred to it, whilst the coo or if such "used, is freed of a corresponding part of its work. v To have my invention fully understood I have illustrated it on the accompanying drawing by way of an example. v

A ump 3 inserted between a feeding tank 1 and the heating system 2, passes themilk -through the heating system and therefrom through a tube 4, provided with a pressure valve 5 into the evaporation or boiling chamber 6 which is exposed to about ordinary pressure through a tube 7 leading into the open feeding tank 1.

The bottom of the chamber 6 is connected with the feeding tube of the pump 3 through a tube 8 provided with a float valve or the like 9 by means of which a suitable milk level is maintained in the chamber 6.

From the lower part of the chamber 6 or the milk space a tube 10 leads to the cooler 11 and therefrom through a valve or cock 12 to one or more canning places or the likenot shown on the drawing.

When passing the ressure valve 5 the milk heated up to a out 130 centigrade Wlll boil, and the vapours thus developed at about 100 centigrade, pass through the tube 7 to the tank 1 where the vapours become condensed in the fresh milk.

If the valve or cook 12 is closed, or if the milk quantity circulated by the pump 3 exceeds the milk quantity being canned, the nnlk level will rise When the milk level is sufficiently high the float valve 9 is opened and the milk is returned by the tube 8 to the pump so as to circulate again through the heatlng'system.

If in a given moment the milk quantit canned exceeds the quantity of hot milk s1- multaneously passing the heating system, no damage or inconvenience will result as the milk capacity of the chamber 6 is sufciently great to equalize the diflerence.

The necessary pressure for passing the milk through the cooler and the canning devlces or the like, may be obtained by arranging the chamber 6 as an upper or overhead cistern so that the tube 4 connectin it with the heating system, is a rising tu e, while the tube 10 connecting it with the cooler, is a dro tube. Moreover the heating s stem an if desired also the cooler, may e arranged in the same hei ht as the evaporating chamber and the may be arranged after the cooler. The pressure valve 5 ma be arrangedat a suitable point of the tu behind the heating system.

One or more check valves 13 in the feeding conduit, prevent back flow of the milk.

The float valve or the like 9 ma be regulated in such a manner that the a ove mentioned closed circulation of the milk through the heatingsystem takes place to such an extent that normally only one third to one sixth of the milk quantity circulated through the heating system passes to the cooler.

When working in this manner that is by repeatedly passing the liquid through the heating system the resent plant may be used for the production of condensed milk or the like, the tube 7 being in this case omitted so that the milk vapours are not condensed in the fresh or circulating milk rop tube 4, if desired directly,

llU

(but allowed to escape to the ,air to a con-.

denser oflower pressure. I claim:

A process for sterilizing milk or a simi- 5 lar liquid by continuously passing the liquid through a heated tube system or the like under pressure, characterized in passing the liquid when leaving the heating system, through a chamber of lower pressure and condensing the vvapours thus developed in NIELS JONAS NIELSEN.

Witnesses:

. \VM. CoUEL,

A. CHRISTAFFERSEN. 

